Objective To compare the testing results of blood gas analysis collected from the same patients with the same blood sampling sites , by no anticoagulant , heparin sodium (100 IU/ml normal saline)and solid lithium heparin .Methods Randomly collected samples from 150 ICU patients by three different hemostix to implement arterial blood gas tests , detected the blood pH , PaCO2 , PaO2 , HCT, Hb, BE, HCO3-,Na+,K+, Ca2+,Lac.Results The test results of arterial blood specimens ( pH, PaCO2 , PaO2 , HCT, Hb, BE, HCO3-, Na+,K+,Ca2+,Lac) of 100 general anesthesia surgery patients in three groups were compared .There were no statistically significant differences between the test results ( F=0.150,0.298,0.052,0.193,0.163,0.364, 0.375,0.874,0.205,2.313,0.059, respectively; P>0.05).The test results of arterial blood specimens of 50 critical patients showed no significant differences ( F=0.007,0.014,0.023,0.006,0.003,0.008,0.009, 0.150,0.023,0.012,0.002, respectively;P>0.05).The lowest and the highest value of ICC were 0.946 and 0.999, with 95%CI (confidence interval) 0.896-0.999 (P〉0.05).Conclusions The test results by three different anticoagulant methods show no statistically significant difference .Three methods are suitable for arterial blood samples to apply blood gas analysis . Key words: Arterial blood gas test; Anticoagulant method; Heparin sodium; Solid lithium; No anticoagulant